Olivetti and AT&T to take a 24.5% stake each in Italtel SpA in return for Italtel’s parent, state-owned Stet, taking over the shares in Olivetti held by Carlo de Benedetti’s Compania Industriale Reunite SpA while he pursues his Belgian campaign. That’s the gossip that has been filling the Italian papers for two or three weeks now, and is becoming so persistent that there is likely to be some truth in it. After failing to merge it with Telettra, Stet needs a foreign firm to inject technology into Italtel, and AT&T wants to expand in Europe. Two flies in the ointment: AT&T’s Olivetti pact requires Carlo de Benedetti to retain control to 1996; and Carlo isn’t Italtel chief Marisa Bellisario’s favourite person…